I don't know, but perhaps someone here does. I have held synchro cones and hubs in my hand, but didn't ever think to look.

Is the synchro action on cone type synchro asymmetric? For example stronger on downshift than upshift (since in normal driving upshifts easier.) Since cone type generates the torque from ridges on cone dragging through lubricant, an engineer could increase the downshift force at the expense of upshift force by shaping the ridges for more drag in one direction.

 

This tranny is designed differently than most trannies. Two things were done in the design to "ensure an exhilarating and quick shifting performance that meets the drivers spirited operation".

1) Normal manual transmissions have a gear reduction prior to transmitting the power to the gear selection, thus reducing the rotational speed of the gears and shafts and synchros. The S2000 transmission has the gear reduction after the gear selection. Thus the gears and shafts and synchros have a higher rotational speed. So skipping gears will be harder on the synchros of this transmission than most.

2) The S2000 transmission was designed to keep the number of number of synchro cones to a minimum. "It is impossible to ensure gear-shift exhilaration only by increasing the synchromizer capacity through the use of a multi-cone, because the shift knob load is not reduced to a satisfactory level".

The engineering of this transmission put a higher emphasis on exhilarating feel and quick performance rather than making it bulletproof (and I'm glad they did).

Quotes are from SAE (Society of Automotive Engineers) Technical Notes "Development of a new six-speed manual transmission", by K. Kitajima, Engineering Development Department 4, Honda R&D.

 

S2WOOOW,

I would love to read this paper, but I can't find it on www.sae.org. Would you please point me to where I can find it?

thanks.

 

I tried finding it with no success. I'm sure I downloaded it, but I can't even find the file on my computer. The document number is JSAE20004052 or 0389-4304. Try the Society of Automotive Engineers of Japan.

 

Found it, thanks.
http://dx.doi.org/10.1016/S0389-4304(99)00085-5

 

Hi;
I have a 2000 S2000 with 77000ms; months ago it started grinding gears in 2nd and 3rd intermittently. Now it shifts fine when engine not started but after starting engine it is diofficult and sometimes won't go into reverse at all.
Any suggestions?

Thanks,
Duncan Temple
Phoneix, Arizona

duncan@funk.com
480-816-4282

 

After reading this I do not know if I have a transmission or a clutch problem; would appreciate any tips before I see the dealer !@##$%
2000 S2000, 77000ms; began grinding a little when shifting to 2nd or 3rd. It shifts easy when engine has not been started but after engine has started it is difficult and impossible sometimes to shift into reverse.

Duncan Temple, Phoenix, AZ, duncan@funk.com; 480-816-4282

 

wow great pics!

 

Duncan, I'd say your clutch is dragging (not completely disengaging). You may have other issues, but I'd start with the clutch adj. rod under the dash. It has worked for many of my customers.